add support for embedding templates and other static resources

This feature is disabled by default and can be enabled using the
"bundle" build tag

Fixes #823

Signed-off-by: Nicola Murino <nicola.murino@gmail.com>

internal/httpd/resources_embedded.go

@@ -0,0 +1,33 @@
+// Copyright (C) 2019-2022  Nicola Murino
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published
+// by the Free Software Foundation, version 3.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+//go:build bundle
+// +build bundle
+
+package httpd
+
+import (
+	"github.com/go-chi/chi/v5"
+
+	"github.com/drakkan/sftpgo/v2/internal/bundle"
+)
+
+func serveStaticDir(router chi.Router, path, _ string) {
+	switch path {
+	case webStaticFilesPath:
+		fileServer(router, path, bundle.GetStaticFs())
+	case webOpenAPIPath:
+		fileServer(router, path, bundle.GetOpenAPIFs())
+	}
+}